Overview: LKM Antibody Dilutions TestIntroduction: The LKM Antibody Dilutions Test detects liver kidney microsomal antibodies in dilutions to diagnose autoimmune hepatitis, causing jaundice or fatigue. Aligned with 2023 AASLD guidelines, it uses immunofluorescence assay for high specificity, supporting liver screening. This test is critical for guiding diagnosis, treatment planning, and improving outcomes in immunology for patients with suspected autoimmune hepatitis, particularly in atypical or early cases.
Other Names: LKM Dilution Assay, Autoimmune Hepatitis Dilution Test.
FDA Status: Laboratory-developed test (LDT), meeting immunology standards for diagnostic accuracy.
Historical Milestone: LKM antibody testing began in the 1970s with autoimmune hepatitis research. Dilution-based immunofluorescence methods improved in the 2000s, enhancing diagnostic precision.
Purpose: Detects LKM antibodies in dilutions to diagnose autoimmune hepatitis, guides treatment, and evaluates patients with jaundice or fatigue.
Test Parameters: 1. LKM Antibodies (Dilutions)
Pretest Condition: No fasting required. Collect serum or saliva. Report history of jaundice, fatigue, or liver dysfunction.
Specimen: Serum (SST, 2-5 mL), Saliva (sterile container, 1-2 mL). Transport in a biohazard container.
Sample Stability at Room Temperature: 8 hours
Sample Stability at Refrigeration: 7 days
Sample Stability at Frozen: 6 months
Medical History: Document jaundice, fatigue, abdominal pain, or family history of autoimmune diseases. Include current medications, especially immunosuppressants.
Consent: Written consent required, detailing the tests purpose, autoimmune hepatitis implications, and risks of blood or saliva collection.
Procedural Considerations: Uses immunofluorescence assay with dilution to detect LKM antibodies in serum or saliva. Results are available in 1-2 days, supporting rapid clinical decisions. Performed in laboratories, often for early autoimmune hepatitis diagnosis.
Factors Affecting Result Accuracy: Hemolysis, lipemia, or improper sample storage can affect results. Insufficient sample volume may reduce accuracy.
Clinical Significance: Positive LKM antibodies in dilutions confirm autoimmune hepatitis, guiding immunosuppressive therapy (e.g., prednisone). Negative results may require further autoimmune testing.
Specialist Consultation: Consult a hepatologist for result interpretation and treatment planning.
Additional Supporting Tests: ANA, SMA, or liver biopsy to confirm autoimmune hepatitis diagnosis.
Test Limitations: Dilution increases specificity but may reduce sensitivity; clinical correlation is needed. Other liver diseases may mimic results.
References: AASLD Hepatitis Guidelines, 2023; Hepatology, Manns MP, 2022.
